Problem 7.24 The weekly mean return and volatility of the S&P500 index for the year 1999 are 0.0031 and 0.0255, respectively (see Table 1.13). The sample size for these data is n = 51 (see Table 1.19). From these data estimate the mean return and volatility of the S&P500 index for:

(a) one year.

(b) six months.

(c) Find a 95% confidence interval for the annual volatility. Hint: Refer to Example 7.8.